Modulepolysemy-zoo-0.8.2.0Haskell2010

Polysemy.Final.NonDet

1 type
4 values

Packagepolysemy-zoo-0.8.2.0
Exports5
LanguageHaskell2010
LicenceBSD-3-Clause
SourceNonDet.hs

datadata NonDet (m :: Type -> Type) a

An effect corresponding to the Alternative typeclass.

Constructors

Empty
Choose (m a) (m a)

valuenonDetToError :: Member (Error e) r => e -> Sem (NonDet ': r) a -> Sem r a

Transform a NonDet effect into an Error e effect, through providing an exception that empty may be mapped to.

This allows <|> to handle throws of the Error e effect.

valuerunNonDet :: Alternative f => Sem (NonDet ': r) a -> Sem r (f a)

Run a NonDet effect in terms of some underlying Alternative f.

valuerunNonDetMaybe :: Sem (NonDet ': r) a -> Sem r (Maybe a)

Run a NonDet effect in terms of an underlying Maybe

Unlike runNonDet, uses of <|> will not execute the second branch at all if the first option succeeds.

valuenonDetToFinal

:: (Member (Final m) r, Alternative m)
=> Sem (NonDet ': r) a
-> Sem r a

Run an NonDet effect through a final Alternative

Beware: Effects that aren't interpreted in terms of the final monad will have local state semantics in regards to NonDet effects interpreted this way. See Final.